Basis of Presentation and Summary of Significant Accounting Policies - Additional Information (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) segment unit	Sep. 30, 2019 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Number of operating segments | segment			1
Number of reportable segments | segment			1
Amount deposit accounts exceeded FDIC insured limit	$ 321,200,000		$ 321,200,000
Amount of short-term marketable securities	118,309,000		$ 118,309,000			$ 116,539,000
Risk pool surplus or deficits, settlement period after risk pool performance year			18 months
Allowance for doubtful accounts	1,300,000		$ 1,300,000			2,900,000
Impairment of finite-lived intangible assets			0	$ 0
Impairment of long-lived assets			$ 0	0
Number of main reporting units | unit			3
Impairment of goodwill	0		$ 0
Impairment of indefinite-lived intangible assets	0	$ 2,000,000.0	0	$ 2,000,000.0
Risk pool settlement	19,800,000		19,800,000
Payments received, monthly			7,600,000
Payments received	22,900,000		68,400,000
Accrued contract liability recognized	14,800,000		57,300,000
Contract liabilities	12,252,000		12,252,000			$ 8,892,000
Contract liability repaid, capitation received and not earned			$ 8,500,000
Investment deposit					$ 4,000,000.0
Voting rights held (more than)			50.00%
Accounts Payable and Accrued Expenses
Summary Of Significant Accounting Policies [Line Items]
Accrued contract liability recognized			$ 400,000
PMPM Managed Care Contract
Summary Of Significant Accounting Policies [Line Items]
Contract term			one year
Management Fee Income Contract
Summary Of Significant Accounting Policies [Line Items]
Contract term			10 years
CMS
Summary Of Significant Accounting Policies [Line Items]
Expected period of payment upon termination of agreement			30 days
Minimum
Summary Of Significant Accounting Policies [Line Items]
Short-term marketable securities, maturity period			4 months
Maximum
Summary Of Significant Accounting Policies [Line Items]
Short-term marketable securities, maturity period			24 months
Certificates of Deposit
Summary Of Significant Accounting Policies [Line Items]
Amount of short-term marketable securities	$ 118,300,000		$ 118,300,000